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1.
In this Note, we shall consider the Riemannian distance on loop groups, which will be identified to one introduced by Hino and Ramirez [M. Hino, J.A. Ramirez, Small-time Gaussian behavior of symmetric diffusion semigroups, Ann. Probab. 31 (2003) 1254–1295]. A transportation cost inequality is established. To cite this article: S. Fang, J. Shao, C. R. Acad. Sci. Paris, Ser. I 341 (2005). 相似文献
2.
Many aspects of the behavior of surfactants have not been well understood due to the coupling of many different mechanisms.
Computer simulation is, therefore, attractive in the sense that it can explore the effect of different mechanisms separately.
In this paper, the shapes, structures and sizes of sodium dodecylbenzenesulfonate (SDBS) micelles under different concentrations
in an oil/water mixture were studied via molecular dynamics (MD) simulations using a simplified atomistic model which basically
maintains the hydrophile and lipophile properties of the surfactant molecules. Above the critical micellar concentration (cmc),
surfactant molecules aggregate spontaneously to form a wide variety of assemblies, from spherical to rodlike, wormlike and
bilayer micelles. Changes in their ratios of the principle moments of inertia (g1/g3, g2/g3) indicated the transition of micelle shapes at different concentrations. The aggregation number of micelle is found to have
a power-law dependence on surfactant concentration. 相似文献
3.
We provide criteria for the strong ergodicity of regime-switching diffusion processes. Our conditions are imposed on the coefficients of the processes. Particularly, we show that for regime-switching diffusions on the half line, if the corresponding diffusion on each fixed environment is strongly ergodic, then the regime-switching diffusion is strongly ergodic as well, which does not depend on the changing rate of the environment. Moreover, the converse is not always true, which is shown by an example. For transience, recurrence and positive recurrence, there is no such good consistency [R. Pinsky and M. Scheutzow, Some remarks and examples concerning the transience and recurrence of random diffusions, Ann. Inst. Henri. Poincaré 28 (1992) 519–536]. 相似文献
4.
提出了一种求解传输线方程的高精度龙格-库塔(RK)方法。此方法在空间上采取高阶泰勒展开,提高了对空间微分的近似精度,减少了数值色散所带来的误差。与传统的时域有限差分法(FDTD)方法相比,在每波长采样数相同时,RK方法的计算精度更高。同时,根据Taylor模型,对外界平面波激励源进行离散,成功利用RK方法对外部场激励传输线进行求解,扩大了龙格-库塔方法在求解传输线方程时的应用范围。通过编程对平面波辐照下无限大地平面上的单导体与双导体的算例分别应用FDTD方法与RK方法进行了计算,验证了RK方法的正确性。结果表明同等计算条件下RK方法的计算精度更高。 相似文献
5.
行人流连续模型直观地反映人群疏散过程中的疏散特征,本文基于行人流连续模型。研究行人在典型疏散场景下的疏散特征.在COMSOL中建立行人流连续模型及其方程,通过编写MATLAB代码,实现了连续模型及其循环求解框架.利用快速扫描法求解Eikonal方程得到背景场值,在每一步迭代循环中将背景场值作为模型的初始变量导入,调用COMSOL计算模块求解模型的瞬态控制方程.通过两个标准算例,重现了典型的行人流自组织现象,验证了连续模型的合理性.结果表明,本文的疏散仿真分析模型和计算程序是可靠的,疏散仿真分析可以为实际工程中的人员疏散方案的制定以及平面设计与安全布置等方面提供技术支撑. 相似文献
6.
TANG Dexiang GE Wei WANG Xiaowei MA Jingsen GUO Li & LI Jinghai Multi-phase Reaction Laboratory Institute of Process Engineering Chinese Academy of Sciences Beijing China 《中国科学B辑(英文版)》2004,47(5):434-442
Particle methods such as SPH (smoothed particlehydrodynamics)[1,2], DEM (distinct-element model)[3],DPD (dissipative particle dynamics)[4— and pseudo- 6]particle modeling (PPM)[7,8] are getting more and morepopular as numerical methods in material science andfluid dynamics, due to their flexibility in simulatingcomplicated phenomena like fluid-solid coupling,multi-phase flow and large deformation and rupture insolid materials. However, a comm… 相似文献
7.
正Supported by the Sino-German Center for Research Promotion,an organization jointly founded by the National Natural Science Foundation of China (NSFC) and the German Research Foundation 相似文献
8.
Feiguo chen Wei Ge Li Guo Xianfeng He Bo Li Jinghai Li Xipeng Li Xiaowei Wang Xiaolong Yuan 《中国颗粒学报》2009,7(4)
mputing mode. The preliminary applications of this machine in areas of multi-phase flow, molecular dynamics and so on are reported, demonstrating the supercomputer as a paradigm of green computation in new architecture. 相似文献
9.
Jihui Lang Xue Li Jinghai Yang Lili Yang Yongjun Zhang Yongsheng YanQiang Han Maobin Wei Ming Gao Xiaoyan Liu Rui Wang 《Applied Surface Science》2011,257(22):9574-9577
ZnO quantum-dot chains codoped with Eu3+ and Er3+ were synthesized by the chemical precipitation method and the codoping effects on the structures, morphologies and optical properties of the powders were briefly investigated. The X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS) results indicated the Eu3+ and Er3+ were incorporated into the crystal lattice of ZnO host. Transmission electron microscope (TEM) measurements showed the sizes of the ZnO quantum dots decreased with the increase of Eu3+ and Er3+ doping concentration, and the quantum-dot chains were formed by codoping with Eu3+ and Er3+. The green emissions in the photoluminescence spectra were attributed to 4f-4f of Er3+ inner shell 2H11/2 → 4I15/2 and 4S3/2 → 4I15/2 transitions, and the characteristic red emissions of Eu3+ ions were attributed to the 5D0 → 7F1 and 5D0 → 7F2 transitions, respectively. Moreover, the red emission of the Eu3+ ions gradually decreased with the Er3+ ions doping concentration increased, which may be due to the different energy storage centers in the powders. 相似文献
10.